At 4 p.m. ET, Keith was 50 miles south-southeast of Chetumal, Mexico, and 40 miles northeast of Belize City. Belize is a small country tucked just below Mexico’s Yucatan pennisula, north of Honduras and west of the Carribean Sea.

“Half of the circulation of this hurricane is over land and half over sea,” said Jamie Rhome, a meteorologist with the Miami-based National Hurricane Center. “For the next 12 hours we expect little motion as it slowly drifts northwest.”

Keith dropped from a Category 4 Hurricane to a Category 3 today, but it was still packing winds of 125 mph.

In southeastern Mexico, officials scrambled to evacuate 5,000 people from low-lying areas in the city of Chetumal on the Yucatan peninsula, while the small carribean country of Belize also prepared to feel the brunt of the storm.

In Mexico, Setting up Shelters

Authorities in Mexico prepared for the worst, setting up 15 shelters and
evacuating 800 people from high-risk areas in the region of 200,000
people, which includes Chetumal, about 190 miles south of Cancun.

Maria de la Cruz, from the nearby community of Izcalac,
abandoned her shack Saturday with her husband, five children and
four other relatives.

“They told us it’s going to hit hard,” said De la Cruz, one of 217 area residents sleeping at a school in Chetumal. “Thank God we have some place to go.”

Others stocked up on bottled water, groceries, flash lights, and
supplies. Hotels taped up their windows.

In southeastern Mexico, families waded down the streets in ankle-deep water. Others rode their bikes through the pounding rain, while old men drank
coffee along a covered sidewalk.

Forecasters warned of possible flash floods and mudslides,
although the slow-moving hurricane was expected to weaken as it
drifted farther inland.

“We’re listening close to the news to see what happens,”
Escamilla said. “We can always buy things if we lose them, but
protecting ourselves is the most important thing.”

Although Keith was in the Caribbean, two of the country’s major oil shipping ports in the Gulf of Mexico were on hurricane alert, port officials told Reuters.

The Pajaritos oil export terminal in Veracruz state and Dos
Bocas port in the state of Tabasco have been closed since
Tuesday because of bad weather and remained closed.

Belize Battens Down

The strongest winds near the core of the powerful hurricane struck northeastern Belize today, ripping away a wind measuring instrument and toppling
over power poles farther south in Belize City.

The U.S. government issued a travel warning earlier today recommending that American citizens evacuate the country.

Emergency officials were concerned about San Pedro, a tourist resort with hotels on Ambergris Cay, a small barrier island the width of three football fields just off Belize.

About 300 American medical students remained at St. Matthews University School of Medicine on Ambergris Cay.

University president Jeffrey S. Sersland said most of the buildings’ structures are sound and everyone on the island has sought shelter inside. Water and electricity to the island was cut off earlier today.

“It’s been very windy,” Sersland said via cell phone today and added that the island has enough supplies to last three or four days.

Watching Two Other Storms

Forecasters were watching two other tropical weather
systems today.

Tropical Storm Joyce, a weak storm system with top winds of
just 40 mph, was moving over Grenada, a southeastern
Caribbean nation of about 98,000 people just north of Trinidad
and Tobago. It was expected to move into the open Caribbean Sea
later today, skirting the South American coast.

It was moving to the west-northwest at about 16 mph
and was expected to stay on that track for the next day,
forecasters said. The storm was spreading heavy rain over
Grenada and small nearby islands but was expected to do little
damage.

Tropical storm warnings were in effect for Grenada, St.
Vincent and the Grenadines.

Far to the north, Tropical Storm Isaac was weakening over
the cooler waters of the North Atlantic.

Its center was about 835 miles west of the
westernmost Azores Islands at latitude 41.6 north and longitude
43.8 west, forecasters said.

Isaac was moving to the east-northeast at about 30 mph
and had top winds of about 70 mph .

The Associated Press, Reuters and
ABCNEWS’ Ed Bailey contributed to this report.